On Saturday, the U.S. National Highway Traffic Safety Administration said that it is opening an investigation to determine why air bags failed to deploy in crashes, after four deaths were reported in Hyundai and Kia vehicles. The agency said it was reviewing over 400,000 Kia Forte cars and 2011 Hyundai Sonata cars. The NHTSA will also determine if any other manufacturers used similar air bag control units.
